A number of drug dealers switched to alternative trading site Dream Market, changed their names, and changed the PGP - the encryption used on communications between dealers and customers. According to the researchers, this shows some degree of panic. "Sellers do not change their PGP key or sales name if they do not think that it is really necessary", the researchers concluded.

In total 20 percent of the drug traffickers that switched to Dream Market changed the name of their online store. And 14 percent changed their PGP key. About 100 dealers kept their names. Only 12 kept both their names and their PGP key.

In June the Dutch police took over the dark web market Hansa - the biggest online drug market, according to NU.nl - after the arrest of the site's administrators. The police kept the site online for a month, keeping track of transactions, and so managed to obtain information on both sellers and buyers. Tens of thousands of Hansa customer addresses were forwarded to Europol.